Finding the Fourth Proportional to 91,961.91, 138,039.39 and 81,498.87

Step by Step Solution

1. Step 1: Write the proportion equation
   91,961.91 : 138,039.39 = 81,498.87 : x
2. Step 2: Convert to fraction form
   91,961.91/138,039.39 = 81,498.87/x
3. Step 3: Cross multiply
   91,961.91x = 138,039.39 × 81,498.87
4. Step 4: Simplify right side
   91,961.91x = 11,250,054,300.49
5. Step 5: Solve for x
   x = 11,250,054,300.49/91,961.91
6. Step 6: Final answer
   x = 122,333.85